Tilting chair construction



May 5, 1964 F. LIE 3,131,904

TILTING CHAIR CONSTRUCTION Filed July 25, 1961 2 Sheets-Sheet 1 5 7 .324 3 46 I 56 42 2: I 1 I rev 5 L l r92 i 104 90 3 40 42 76 76 40 9 34INVENTOR. F/G. 3 F/NN L/E ,47'TOENE V5 May 5, 1964 F. LIE

TILTING CHAIR CONSTRUCTION 2 Sheets-Sheet 2 Filed July 25, 1961 BYMLso/v, 557715 & CRAIG mu 6 m F z w a w L w 1% E w fl W fi /flz I,

ArrozA/E Y5 United States Patent 3,131,904 TILTING CHAIR CONSTRUCTIONFinn Lie, Ring ti ration, near Hamar, Norway Filed July 25, 1961, Ser.No. 126,643 4 Ciairns. (Cl. 248-373) This invention relates to tiltingchair constructions, as for example, ofiice chairs, and moreparticularly to an iron for a tilting chair that utilizes a torsion barfor resiliently restraining the backward tilting of a chair seat as aperson, sitting in the chair, shifts his weight to tilt the seat back. V

A great many of the tilting chair iron constructions of the prior arthave utilized heavy castings and coil springs in their construction. Thecoil springs are bulky and require sockets of appreciable size to retaintheir ends. Further, in order to adjust the tension of the springs,controlling the tilting movement of the chair, an adjusting mechanism ofsome sort, usually comprising a yoke and threaded handle springtensioner assembly, has been required. The sum total of theserequirements have found the prior art products to be of substantial bulkand characterized by various knobs, springs, plates, sockets, etc.,which require an extended assembly time, generally resulting in a largeunit, lacking in aesthetic appeal for consumers.

Accordingly, it is an important object of the present invention toprovide a novel, tiltable chair iron' utilizing a torsion bar to providea resilient restraining force for the tilting movement of the chairseat, as a neat, precise and compact unit.

Another object is to provide a tiltable chair iron which utilizesstamped parts in its construction, that are readily assembled with aminimum amount of labor, and that has long life substantially free ofmaintenance.

A further object is to provide a tiltable chair iron uti1iz ing atorsion bar wherein the two ends of the torsion bar are provided withstops whereby the parts bearing against the torsion bar are not securedto the torsion bar, thus substantially reducing the assembly time of theunit.

A further object is to provide a tiltable chair iron utilizing a torsionbar wherein a spindle socket support mounted on the torsion barcooperates with a seat frame support to establish the pivotal limits ofmovement of the chair seat which is mounted upon the assembly.

A still further object is to provide a tiltable chair iron utilizing atorsion bar wherein a simple tensioning arm of neat appearance isinterposed between one end of the torsion bar and a seat support toprovide adjustment of the tension of the torsion barand thereby adaptthe chair to use by occupants of differing weight.

Other objects of this invention will appear in the following descriptionand appended claims, reference being had to the accompanying drawingsforming a part of this specification wherein like reference charactersdesignate corresponding parts in the several views.

- In the drawings:

- FIG. 1 is an elevational view of a chair incorporating an iron made inaccordance with the present invention;

FIG. 2 is a bottom plan view of the present chair iron construction; i

FIG. 3 is a front view, partially in section, taken along the lines 33of FIG. 2, loohng in the direction of the arrows; V

FIG. 4 is a section view taken along the line 44 of FIG. 2, looking inthe direction of the arrows;

FIG. 5 is a side elevational view of FIG. 2, taken along line.55 of FIG.2; and

FIG. 6 is a section view taken along the line 66 of FIG. 2, looking inthe direction of the arrows. if

Before explaining the present invention in detail it is ice to beunderstood that the invention is not limited in its application to thedetails of construction and arrangement of parts illustrated in theaccompanying drawings, since the invention is capable of otherembodiments and of being practiced or carried out in various ways. Also,it is to be understood that the phraseology or terminology employedherein is for the purpose of description and not of limitation.

Briefly the present invention relates to a new and improved tiltingchair iron construction that utilizes a pair of spaced seat supportsthat are carried by a pair of aligned frame tubes, spaced at their innerends by a separator carrying a stop member. A torsion bar tube ispositioned within the frametubes in rotatable relation and a torsion baris positioned coaxially within thelatter tube. The torsion bar isconnected at one end to one end of the torsion bar tube and extends thecombined length of the frame tubes. An adjustable tensioning arm isconnected to the other end of the torsion bar and is provided with astop adapted to engage one of the seat supports.

A spindlesocket support is rotatably mounted on the torsion b'ar tubewithin the separator for the frame tubes and is provided with anabutment to engage an abutment on a torsion bar tube. Also, the spindlesocket support is provided with stops which establish the limits oftilting movement of the seat" supports.

Thus pivoting of the seat support and frame tubes about the torsion bartube is effective to move the tensioning arm and thus impart a-twist tothe torsion bar that biases the torsion bar tube more firmly against theimmovable spindle socket support to provide a resilient pivoting support'of thechair seat and engagement of the chair seat stop member with thespindle socket support stops to establish the limits of movement of thechair seat.

THE ENVIRONMENT As shown in FIG. 1, a chair structure, utilizing atorsion bar iron of the present invention, includes a floor engagingbase 10 having outwardly extending legs 12 supported at their lowerterminal ends by rollers 14 for moving the unit about. Centrally of thebase 10 there is provided a vertically disposed spindle 16 having anexposed upper end of tapered configuration (not'shown). The upper end ofthe spindle projects into a tapered socket 18 which is a part of thecentral support assembly 20,-FIG. 2, of the chair iron 22. A chair seat24 is mounted upon the iron 22 for rearward pivotal movement againstresiliently restraining forces imparted by a torsion bar, to besubsequently described, which forms a component part of the iron. Arms26 and a back 28 of suitable configuration are mounted on the seat 24 ina conventional manner to complete the chair structure.

I THE NOVEL IRON As shown in the detailed views of FIGS. 2-6, the iron22 includes a pair of spaced seat-supporting angles 30,

each having a vertically disposed leg 32 and a horizontally disposed leg34. The horizontally disposed legs 34 are provided with apertures as.at36, suitably formed by drilling, punching or the like, through whichbolts or other suitable fastening devices (not shown) can be passed forconnection with a chair seat 24, previously FIGS. 2 and 3, assembly ofthe unit is such that the spaced, seat-supporting angles 30 are inaligned relationship.

Centrally of the spaced seat-supporting angles 30, there is provided agenerally square spacer and stop member 44 having vertically disposedsides 46, a vertically disposed front 48 anda vertically disposed back50. The sides 46, front 48 and back 50 are suitably fabricated from onepiece of strap steel of rectangular cross section, as indicated in'FlG.3, the ends of the strap being joined as by welding (not shown) afterformation of the unit 44 is completed. As best shown in FIG. 4, aportionof the vertically disposed back 50, in the centralpart thereof,is turned back' from the top to provide a stop lip 52, that is fittedwith aresilient stop cushion 54, suitably formed of nylon. The metal ofthe vertically disposed back 50, remaining beneath the stop lip 52, isbowed outwardly as indicated at 56 to stiffen the stop lip 52. v Thevertically disposed sides 46 are provided with apertures 58 adapted toreceive the inner ends of. the support tubes 40, which arewelded as'at42,: to provide a rigid assembly made up of the spaced, seat-supportingangles 30, the support tubes 40 and the square spacer and stop member44. This assembly supports a chair seat24 and cooperates with a torsionbar unit carried withinthe support tubes 40 to resiliently restraintilting movement ofthe. chain seat between a horizontal 1 position and atilted position. v a

Theiron also includes the p'erviou'sly mentioned central support.assembly'20 that, as best shown in .FIGS. 4

and 6, comprises a lower U-shaped yoke 60 having vertically disposedarms 62, and an upper U-shaped yoke64 having .verticallvdisp sed arms 66fitting in adjacent relationship inside of the arms'62. Riverts 68 areinserted through aligned apertures formed in the arms 62 .and 66 tosecure the' assembly. The previously mentioned tapered socket 18 isfitted into suitable apertures 70 and 72 formed in the lower yoke 60 andthe upperyoke 64 and is fastened in position by tack welding or theequivalent, as shown at 74 in FIG. 4.

As shown in FIG. .4; the vertically disposed arms 62 of the lowerU-shaped yoke 60 extend rearwardly in the shape of enlarged supportingtabs 76, also shown in FIG. 2. The support tabs 76 are provided withapertures 78 in aligned relationship asshown in FIG. 2, and an elongatedtube 80 is passed therethrough and within support tubes 40, enoughclearance being provided to permit free rotation. As best shown in FIG.4 a key 82.isinserted in secured relationship into a suitable aperture;provided in the tnbe80l Also, as shown in FIG. 4, the upper U- shapedyoke 64 extends rearwardly as an abutment tab 85 which is aligned withthe key82, to be engaged thereby'and'thus' absorb tube thrust andtransmit the thrust into the central support assembly 20, tapered socket'18, the chair spindle, the chair base, etc., thus to the surface uponwhich the chair rests. This configuration of parts permitsassemblywithout welding.

When the parts are assembled, as shown in FIG. 4, the stop lip 52,previously mentioned, projects between the underside of the upper,U-shaped'yoke 64 and the upper surface. of, the lower, U-shaped yoke-60.This provides upper and lower stop limitsfortilting movement of thechair seat.

1 As best shown in'FIG, 3,1the tube: 80 has substantially the samelength as the distance between the terminal ends of the tubes 40 but ispositioned to extend outwardly from the left end of the left tube. 40,so thatthe right end lies at a point 86, whichisa short distance insideof the right end of the right tube 40. The left end of the tube" 80 isplugged and the plug is provided centrally with a square opening 88 intowhich the terminal end of a square torsion bar 90 is fastened.

The torsion bar90 extends the full length of the inner,

elongated "tube 80, as well as the full length of the outer support"tubes 40 and projectsya short distance beyond t r ht hand end, of the'righthandtube 40 o provide a shoft connecting portion 92.

As best shown in FIGS. 2 and 5, a tensioning arm 94 is provided at itsrear end with a circular bushing portion 96, having a square hole formedcentrally thereof for receiving the right hand end of the torsion bar90, including the short connecting portion 92. The circular bushingportion 96 has an outside diameter slightly less than the insidediameter of the tube 40 and thus is supported in rotatable, journaledrelationship therein. The front end of the tensioning arm 94 is providedwith a horizontally disposed tab portion 98 provided with a threadedaperture, adapted to receive the threaded end 100 of an adjusting ortensioning crank 102. The threaded end 100 of the tensioning crank 102terminates in a contacting ball portion 104, FIGS. 3 and 5, that abutsthe underside of the horizontally disposed leg 34 of the right supportangle 30. The other end of the crank '102 takes the form of-an offsetarm 105 having a knob 106 fastened thereto.

, FUNCTION OF THE APPARATUS support assembly 20 and the arms 76 thereofalso em brace the elongated tube 80 to support the tube in space. Thus,the vmechanism including the square spacer. and stop member 44, support.tubes 40 and angles are supported in space to support the chair seat.

When, as shown in FIGS. 4 and 5, a personoccupies V the chairand tiltsthe rear portion of the seat downwardly and rearwardly, two actions takeplace. 'The first action 1 is the pressing-of the horizontal leg 34 ofthe right support angle 30 against the contact portion 104 of the crank102 to carry the tensioning arm 94 downwardly, causing the torsion bar90 to be twisted, thus turning the elongated tube 80 and forcing the key82 into tighter engagement 1 with the abutment tab 84, which isimmovable, thus providing a resilient, restraining action for thedownward tilting of the chair seat. During the downward and rearwardtiltingof the chair seat, the stop lip.52, carrying the resilient stopcushion 54, moves from contacting relationship with the underside of theupper, U-shaped' yoke ADJUSTABILITY FEATURE By means of the tensioningcrank 102, the resilient restraining force provided by the torsion bar90 can .be adjusted. Thus, as shown in FIG. 5, turning the'crank 102 tomove the horizontal tab portion 98, of the, tensioning arm 94 upwardlywill have the efiectof reducing the pretwist'imparted to the torsion bar90 and thus will permitthe chair to be tilted with less weight or'force.

' On the other hand, adjusting the crank 102 to pull the tensioning arm94 downwardly will serve to impart a greater pretwist to thetorsion'bari90 and accordingly 2. larger weight or force be required tomove the chair seat downwardly in a tilting manner. adapted to use bypersons of different weight. i

MATERIALS OF CONSTRUCTION u The stampings utilized in the presentconstructionwill be formed of steel as will the support tubesf Also, thespindle. socket will be made of steel. The torsion bar will be made ofsteel of a suitable resiliency. to provide a supportingstructure andwill be of a metal which will resist torsionalbending throughout alonglifetime. The tensioning arm maybe madeas a casting, forgi.ng,.iorstamping,- of suitable. steel. .The adjusting or tensioning crankwill bemade of cold rolledsteel rod stock or the equivalent and the knob' ofsimilar material. The re,

Thus the iron silient stop cushion 54 is suitably formed of nylon, asmentioned, although other resilient materials, such as rubber andplastics or synthetic resins of resiliency characteristics similar tonylon can be utilized.

SUMMARY In View of the foregoing it will be observed that an improvedchair iron of the tilting type is provided that utilizes a torsion baras a resilient restraining member, and that comprises a minimum numberof parts, including simple stampings and tubing, readily and simplyassembled with a minimum amount of labor, including only a small amountof Welding and a minor amount of riveting. Thus substantialmanufacturing economies are provided for a clean, compact unit,characterized by long, trouble-free operation, substantially withoutmaintenance.

I claim:

1. In a tilting chair iron, a seat support comprising two laterallyspaced frame elements, a pair of support tubes, each of said tubeshaving one end connected to one of said frame elements, the other endsof said tubes being connected to a spacer with the tubes in axialalignment, said spacer being effective to space the other ends of saidsupport tubes 2. short distance apart, a torsion bar tube positionedwithin said support tubes in rotatable relation therein, a spindlesocket support rotatably mounted on said torsion bar tube within saidspacer and between the other ends of said support tubes, a key in saidtorsion bar tube engageable with said spindle socket support, anelongated torsion bar within said torsion bar tube, said torsion barbeing connected to said torsion bar tube at one point, and adjustableabutment means carried by said torsion bar and spaced from said onepoint and contactably engaging said seat support.

2. In a tilting chair iron, a cushion-supporting frame element, asupport tube connected to said frame element, a stop connected to saidsupport tube, a torsion bar tube positioned within said support tube inrotatable relation, a spindle socket support rotatably mounted on saidtorsion bar tube, first and second spaced abutments on said spindlesocket support engageable with said support tube stop, means on saidtorsion bar tube engageable with said spindle socket support, a torsionbar within said torsion bar tube, means connecting a first point of saidtorsion bar to said torsion bar tube, and an arm connected to a secondpoint on said torsion bar and freely engaging said frame element.

3. In a chair iron,

a seat support comprising two laterally spaced frame elements,

a pair of support tubes, each of said tubes having one end connected toone of said flame elements,

said tubes being positioned in coaxial alignment with the other end ofeach tube connected to a spacer,

said spacer being effective to separate the other ends of said supporttubes,

a torsion bar tube extending within said support tubes in rotatablerelation and spanning said spacer,

a spindle socket support rotatably mounted on said torsion bar tubewithin said spacer and between the other ends of said support tubes,

a key abutment on said torsion bar tube contactably engageable with saidspindle socket support,

a torsion bar within said torsion bar tube,

said torsion bar being connected to said torsion bar tube at one end andprojecting beyond the other end of said torsion bar tube to be exposed,

an arm rigidly connected at one end to said torsion bar exposed end,

an aperture in the other end of said arm,

and a threaded rod in said aperture and having one end engageable withone of said frame elements.

4. In a tilting chair iron,

a seat support comprising two laterally spaced frame angles,

first and second support tubes, each of said tubes having one endconnected to one of said frame angles,

said tubes being positioned in coaxial alignment with the other ends ofsaid tubes attached to a connector,

said connector being efiective to separate the other ends of saidsupport tubes and provide a space therebetween,

a torsion bar tube positioned within said support tubes in rotatablerelation therein,

a spindle socket support rotatably mounted on said torsion bar tubewithin said connector space, between the ends of said support tubes,

abutment means on said torsion bar tube contactably engageable with saidspindle socket support,

spaced abutments on said spindle socket supports,

a stop lip formed on said connector and projecting between andengageable with said abutments,

an elongated torsion bar within said torsion bar tube, said torsion barbeing connected to said torsion bar tube at one point,

and means carried by said torsion bar and spaced from said one point andcontactably engaging a frame angle of said seat support.

References Cited in the file of this patent UNITED STATES PATENTS

1. IN A TILTING CHAIR IRON, A SEAT SUPPORT COMPRISING TWO LATERALLYSPACED FRAME ELEMENTS, A PAIR OF SUPPORT TUBES, EACH OF SAID TUBESHAVING ONE END CONNECTED TO ONE OF SAID FRAME ELEMENTS, THE OTHER ENDSOF SAID TUBES BEING CONNECTED TO A SPACER WITH THE TUBES IN AXIALALIGNMENT, SAID SPACER BEING EFFECTIVE TO SPACE THE OTHER ENDS OF SAIDSUPPORT TUBES A SHORT DISTANCE APART, A TORSION BAR TUBE POSITIONEDWITHIN SAID SUPPORT TUBES IN ROTATABLE RELATION THEREIN, A SPINDLESOCKET SUPPORT ROTATABLY MOUNTED ON SAID TORSION BAR TUBE WITHIN SAIDSPACER AND BETWEEN THE OTHER ENDS OF SAID SUPPORT TUBES, A KEY IN SAIDTORSION BAR TUBE ENGAGEABLE WITH SAID SPINDLE SOCKET SUPPORT, ANELONGATED TORSION BAR WITHIN SAID TORSION BAR TUBE, SAID TORSION BARBEING CONNECTED TO SAID TORSION BAR TUBE AT ONE POINT, AND ADJUSTABLEABUTMENT MEANS CARRIED BY SAID TORSION BAR AND SPACED FROM SAID ONEPOINT AND CONTACTABLY ENGAGING SAID SEAT SUPPORT.